我找不到这个错在那里？请帮忙
create function adduser(username varchar(20))
-> returns int unsigned
-> BEGIN
-> INSERT test（username） VALUES(username);
-> return LAST_INSERT_ID();
-> END
-> //
Query OK, 0 rows affected (0.02 sec)
mysql> select adduser('lisa')//
ERROR 1146 (42S02): Table 'test.test（username）' doesn't exist
mysql> select adduser('lisa')//
ERROR 1146 (42S02): Table 'test.test（username）' doesn't exist
mysql> SELECT adduser('lia')//
ERROR 1146 (42S02): Table 'test.test（username）' doesn't exist
mysql> SELECT adduser('lia')//
ERROR 1146 (42S02): Table 'test.test（username）' doesn't exist
